Internal combustion engine



Dec. 28, 1931. P A. TANNER 2,103,564

INTERNAL COMBUSTION ENGlNE Filed Dec. 19, 1934 Patented Dec. 28, 1937 UNITED ASTATES PATENT ori-ics INTERNAL COMBUSTION ENGINE Philip A. Tanner,A Waukegan, Ill., assigner to Johnson Motor Company, Waukegan, Ill., a

corporation of Delaware Application December 19, 1934, Serial No. 758,176

9 Claims.

.This invention relates in general to a combustion engine and has more particular reference to a multi-cylinder, two-cycle engine of the alternate firing type in which provision is made for bypassing the fuel from one cylinder to the other one, toimprove slow speed running and starting conditions.

tp receive-more than its usual fuel mixture sothat it will be more fully scavenged and result in more perfect combustion.

A further object of the invention is in /the provisionV of va. fuel bypass for an alternate firing engine to enable the elimination of the firing in one of the cylinders an'd to enable the engine to run `more, slowly and surely upon the other cylinder alone.

A further object of the invention is in the provision of improved controlemeans for starting and running an alternate firing two-cycleengine by providingA a fuel bypass connecting the cylinders.

A still further object of the invention is in the provision of means to fully scavenge the cylinder to which the fuel is bypassed, to enable the engine to run slowly and surely at slow speed.

In the accompanying drawing illustrating a preferred embodiment of the invention for accomplishing the foregoing and4 other results,

Figs 1 is a longitudinal sectional view of a two-cycle alternate firing internal combustion engine having a closed crank case with separate compartments for the different cylinders;

Fig. 2 is a section taken on the line 2--2 of Fig. 1; and l Q Fig. 3 is a detail section taken on the line H of Fig. 2. f

vInternal combustion engines of` the two-cycle internal combustion type are commonly used in connection with outboard motors and because they are intended for high speed operation it is sometimes diiiicult to run them slowly and surely for slow speed purposes and the like.

The present invention provides a means particularly applicable to thealternate firing type of engine in which pairsvof cylinders are located adjacent and one above the other. A controlledfuel bypass is provided between the cylinders which is operative to prevent the combustion chamber such as fishing, trolling,

An important object of the invention is in the" (CLI 123-173) ,of one of the cylinders from receiving a fuel d mixture and at the same time 'to provide means for bypassing the fuel-mixture from one cylinder to the other so that the latter will receive a larger charge which will more thoroughly scavenge that cylinder which receives the fuel mixture, resulting in better combustion'and more dependable operation, but operating at slower speed becauseof the decreased power and the retarding friction and load of the cylinder which is vreceiving no combustible mixture.

Referring now more particularly to the draw- -ing, a sectional view of a two-cycle alternate iiring engine is shown in Fig. 1 having upper and lower cylinders 6 and 1 in which pistons 8 and 9 are movable, the pistons being connected by rods gaseous mixture and compressing it therein due to the movement of the piston 8 or 9 in the respective cylinder 6 or l with which the crank case chambers i6 and Il are connected.

Communication is afforded between each of the crank case chambers and its respective cylinder around the piston, in normal operation, by means of a fuel passage I5 and a fuel inlet port I8 in the side wall of the cylinder, the exhaust gases being discharged from the cylinder through an exhaust passage I9 at the opposite side of the cylinder., all in accordance with well-known 2- cycle engine practice. To an engine of this type in which the pistons in adjoining cylinders are connected for alternate firing, that is, at 180 degrees apart on the crank shaft, the present invention is applied. It consists in theprovision of a passage or a bypass 20 formed in the walls between the cylinders and extending from they fuel passage I5 of the upper cylinder and terminating in a port 2| in the other or lower cylinder which is ,uncovered by thel piston 9 therein ,at the outer end of its stroke.

In order to control the closing of the inlet port I8 for the upper cylinder and the bypass, a valve 22 is rotatably mounted-in a recess 23 provided in the wall of the upper cylinder at the end of thebypass 20 and adapted to'close the bypass as shown in full lines in Fig. 3 or to close the passage I5 when the valve is turned at ninety degrees as shown by the broken outline in this figure. This valve 22 has a stem A24 extending through a packing' gnd Vat which hows thef valve in place and atthe ou@ end of the stem l is an operating crank 26 by means of which the valve may be turned or adjusted as desired.

With the cut-out valve closed the engine will operate normally with both cylinders but with the cut-out valve open, that is, to close the ported end of the passage I5 of the upper cylinder, the bypass will be opened between the cylinders which will cause the compressed gases from the upper crank case chamber I6 to flow through the bypass 20 to the suction side of the piston in ,the lower cylinder. When the lower piston has just completed its suction stroke the upper crank case chamber is full of a compressed charge, the lower crank chamber has drawn in a. charge of gas at relatively low pressure, and the uncovering of the port 2| will cause an additional charge of compressed gas to ow from the upper crank case chamber to the suction side of the lower piston, thus filling the lower crank case chamber fuller than usual with a combustible charge at higher pressure so that when compressed by the movement of the lower piston 9 this explosive mixture will bypass around the piston with enough volume to fully scavenge this cylinder, to ll the combustion chamber under higher pressure which will fully scavenge the combustion chamber and will cause good clean combustion when the charge is ignited.

In an engine of this type the crank case chambers I6 and I'I may be separately charged with an explosive mixture from a carbureter in any well known manner, but as illustrated, the partition bearing I4 forms a rotary valve with peripheral inlet ports 30 and 3| with passages 32 and 33 respectively leading therefrom through opposite sides of the portion into the chambers I6 and I'I. A fuel inletl35 through the casing I3 communicates alternately with the ports 30 and 3| for charging the chambers as the bearing valve member I4 is rotated.

With this construction the engine will run on the lower cylinder only, it will run more smoothly at lower speed, it will start easier and the engine may be run more slowly for trolling or fishing, the engine being also retarded by the idle movement of the upper piston in the cylinder, the upper combustion chamber being closed by the valve 2|, thereby causing an obstructive drag upon the piston 8 inboth directions of its movement. The lower cylinder is given a larger charge-and under higher compression than during its normal operation which will assist in starting an engine of this type, in scavenging the lower cylinder of its exhaust gases, and in more fully charging it with a combustible mixture, thereby resulting in improved operation for that cylinder adapting the engine more readily for low speed operation.

I claim:

1. A two-cycle internal combustion engine hav- 2. An internal combustion engine of the twocycle, double-cylinder, alternate firing type com- Drising separate pre-compression chambers and passages therefrom to each of the respective cylinders, a piston movable in each cylinder for controlling the passages, and a bypass between the passages with a valve therein for closing the passage to one of the cylinders and opening the passage from this cylinder to the other cylinder to give the said other cylinder a larger charge than normal.

3. In a two-cycle, two cylinder, alternate firing, internal combustion engine of the crank case compression fuel type having means dividing the crank case and separate compression chambers for each cylinder, a passage from each compression chamber to the outer end of the cylinder, opposite inlet and exhaust passages in the Walls of the cylinder, the passages lbeing controlled by the pistons movable therein, of a transfer bypass between the passages having a port in the wall of one of the cylinders for admitting gas under compression from the passage of the other cylinder in advance of and after the normal fueladmission port flor the cylinder to correspondingly increase the charging thereof.

4. A two-cycle internal combustion engine having adjacent cylinders with separate closed precompression fuel chambers and a separate fuel passage therefrom for each cylinder, of a bypass between the fuel passages for transferring the compressed charge from one compressioncylinder to the other at the end of )the compression stroke to increase the charge in the latter, the

valve in the bypass being manually operable for closing the fuel passage from one chamber to its cylinder and adding the charge therefrom to the other chamber, the cylinder thus cut out causing an obstructive retardation to the engine. l

5. In an internal combustionengine, the combination with pistons, connecting rods, and a crank shaft having cranks with which said con-l necting rods are engaged for consecutive expansion strokes, of charge compressing and expansion l systems individual to the respective pistons, each such system including compression and expansion chambers and an intervening passage, a bypass connecting the said systems, and valve means operable for permanently diverting each successive compressed charge from its normal cycle in one of said systems through said by-pass into the other.

6. A two-cycle internal combustion engine comprising the combination with pistons, connecting rods, and a crank shaft having cranks to which said connecting rods are secured for the consecutive movement of said pistons in their compression and expansion strokes, of charge compression and expansion systems individual to the respective pistons, and each comprising a charge compression chamber, a transfer passage and a combustion chamber, said pistons being operable in the respective chambers of their respective systems to draw a charge into the compression chamber, compress it therein, and respond to the expansion of the charge in the combustion chamber in accordance with the two stroke cycle principle of operation, a by-pass from the said system of one piston to the said systeml of the other, and valve means concurrently controlling transfer to the combustion chamber of the first system and communicatio.A through said i passage to permit the normal cyclic operations of both of `said systems.

. 7. In'an internalcombustion engine, the comsI v bination with-pistons, connecting rods therefor,

and a common crank shaft having cranks to which said .connecting rods are secured for sep--u arate operation; of charge handling systems in- E div'idual to the respective pistons and each inciuding a precompression chamber, a combustion chamber having an exhaust port, and a transfer passageaffording controlled communication be- /tween said chambers; `and a by-pass duct connecting a portion of one of said systems with a portion of the other of saidvsystems, the rst of said systems having valve means adjustable bej tween two positions in the first ofl which' said by-pass duct is closed and each of said systems is open for normal two cycle operation and in the second of which positions said by-pass duct is open and one of said systems is precluded from normal two cycle operation and. a charge compressed therein is diverted to the otherof said systems. A

8. In an internal combustion engine, the comlbination with' pistons, connecting rods, and a crank shaft having cranks with whichsaid connecting rods are Vengaged for consecutive expansion strokes, of. charge compressing and expansion systems individual to the respective pistons;

each such system including cmnpression and expansion chambers served bya common piston and the'intervening passage affording communication tems through said by-pass to augment ansucceeding charge in the other. 9. Inan internal combustion engine, the combinationv l with pistons; connecting rods,A -and a- 'crankshait havingA cranks with which said connecting rods are engaged for consecutive expansion strokes, of a cylinder anda crank case means providing compressing and expansion systems individual tothe respective pistons, each such system including compressio'and expansion'chambers and an intervening passage communicati ing with theexpansion chamber subject to thev 'control of the piston operating therein, a lay-pass connecting the said systems, and valve means.

cci-operating with the piston of one of said systems 'for permanently diverting to-said one system each successive charge compressedin the in through the by-pass into said one system.

1 PHILIP A. TANNER.

25 other of said systems from its normal cycle there- 

